Conventional sickle bars on agricultural machines have a plurality of laterally spaced guards accommodating a reciprocating sickle. The guards have longitudinal bodies that are attached at the rear end thereof to a plate. The sickle comprising a plurality of triangular-shaped knives or sections reciprocates relative to the guards to effect cutting of plants and materials that are located between the guards. The sickle bar is moved adjacent the surface of the ground during the cutting operation. The guards strike the ground and objects, such as stones, rocks, boulders, and like fixed hard objects. The sickle bar must ride over the objects. The impact forces of a guard hitting an object and the weight of the sickle bar and machine as the guard rides over the object subjects the guard to considerable force. The guards, being of malleable iron, will bend and break. Broken guards must be replaced. The bent guards are realigned with the sickle to free up the sickle. The conventional practice is to use a heavy hammer or pipe to pound and bend the guard back to its horizontal position in alignment with the sickle. The use of a hammer applies sharp impact forces to the guard causing considerable breakage of the bodies and lips of the guards.